'Barack Obama, like Princess Diana at the Taj Mahal, knew the key to these picture opportunities was to be alone, communing with the gods of place.' Photograph: Saul Loeb/AFP/Getty Images

Stonehenge is the nearest thing I know to proof of the existence of God, or perhaps gods. This week it made the New York Times not once but twice. Under a harvest moon, its high priests gathered in Birmingham to tell the world of their latest mystical findings – while down in Wiltshire there was a deafening noise. Out of a flying machine stepped the most powerful man on earth. Barack Obama, like Princess Diana at the Taj Mahal, knew the key to these picture opportunities was to be alone, communing with the gods of place. With onlookers panting for reaction, he incanted with the bards: “How cool is this!”

Obama’s helicopter had been on its way back from the Nato summit in Wales when it was drawn by some magnetic force into the “Wiltshire triangle”. The president apparently could not resist a quick look. Motorcades were summoned and the local archdruid, Terry of Avebury, suggested that Nato summits would be less of a shambles if they met amid the magic stones, given their known ability to “clear people’s minds”.

Meanwhile, in Birmingham the stone age hack pack was experiencing what old hands know as the “ceremony of the breathtaking discovery”. This involves unearthing anything to which the archaeology media can attach a “theory”. We learned that “magnetometry, ground-penetrating radar and electromagnetic interference sensors” had detected 17 previously unknown circles, mounds and pits.

Gasping reporters wrote that what had been thought “just green grass” was once “teeming with chapels and shrines, uncovered at last”. Television news showed ragged but strangely clean-shaven actors wandering slowly through mist. BBC2 was in ecstasy.

While something has clearly been detected, including an apparent 33 metre long “mortuary”, the idea that Stonehenge was thought an isolated monument is absurd. Timothy Darvill’s 2006 survey, Stonehenge – The Biography of a Landscape, has the area thick with around 670 similar features.

“At a density of about five barrows per square kilometre,” he says, “this makes it one of the most heavily populated areas of the British Isles in terms of the number of burial monuments.” The greatest concentration is actually round Stonehenge itself.

That Stonehenge was a busy burial site, or at least a place where people were buried, is hardly new. But anything is grist to the Stonehenge theory mill. If only its creators had been up with their Sumerian and Egyptian contemporaries and known how to write, a good deal of trouble would have been saved. But the world would have been deprived of centuries of hokum. From Merlin legends to druid rituals, from wicker men to hippies, from the Pendragons to tour operators, the place has been irresistible.

Stonehenge may not be supernatural, but those who spend their lives peering at it can go mad. The local police and English Heritage have let it become the druids’ Vatican. Champions of mortuaries feud with those of astrology, ancestor worship, stargazing, clock-watching, king’s castles, epidemics and Welsh invaders. The stones themselves were pummelled by the old Ministry of Works to look like a tended municipal rock garden.

The adjacent A303 is certainly cursed. The refusal of Homo sapiens Whitehalliensis to widen the road means an hour-long reverential crawl on summer weekends that will doubtless fascinate Martian archaeologists. In the late 1980s the Ministry of Defence refused to allow a road diversion through its land on grounds of “national security”, clearly a reference to UFOs and other powers. Meanwhile, there are imitation henges everywhere: a carhenge in Nebraska, a fridgehenge in New Zealand, a tankhenge in Berlin. Even American presidents are now spellbound by the mysteries.

But I plumped for Darvill and his partner, Geoffrey Wainwright, as leaders of the “health clinic” school. In October 2006 they held an electrifying seminar at the Society of Antiquaries in London to reveal that the key to Stonehenge lay in the much older curative wells of the Preseli mountains in Wales, known as the source of the circle’s dolerite bluestones.

Healing alone could plausibly explain Stonehenge’s “great question” – why such massive rocks were brought so far by its priestly impresarios. Religion has always known that good business lies in the here and now as well as the hereafter. Monasteries sold themselves as hospitals, and reliquaries were their medicine chests: saving bodies was as profitable as saving souls. Hence the sale of bluestone souvenirs to pilgrims from as far away as the Alps. Stonehenge was, as the tabloids put it, “the A&E of north Wiltshire”. It was not Highgate but Harley Street.

I still find Stonehenge rather dull. When it comes to prehistory, I am more for picturesque Avebury or Brittany’s stupendous Carnac. Wiltshire’s henge is small and fragmentary, and I wish someone would replace the fallen lintels and fill in the gaps.

Another “Stonehenge sensation” this month revealed that the henge had been a complete circle. Given its astronomical precision, why not put it back as intended by its builders? We do not leave sundials out of line or clocks without escapements. We know where the sarsens and bluestones came from. We rebuild churches and cathedrals. A reconstructed Stonehenge might make sense, and not just to archaeologists.

But there we go. Like Obama and the rest, I have communed too long and am probably going mad.